**NY-21 remains a Republican-leaning open seat following Elise Stefanik’s retirement, with registered Republicans outnumbering Democrats by roughly 80,000 and the district backing Donald Trump by 5.5 points in 2024.** Anthony Constantino secured the GOP nomination with 59% in the June primary and has self-funded more than $17 million, enabling heavy advertising while securing Trump’s endorsement and support from groups such as the Fraternal Order of Police. Blake Gendebien won his Democratic primary comfortably and has emphasized rural economic concerns, healthcare access, and cross-border issues with Canada, drawing DCCC investment that has narrowed the contest. Recent Siena polling showed Gendebien ahead by four points in early October, while other surveys indicate a tighter race; forecasters rate the contest Lean Republican. Traders price Constantino’s structural and financial edges at 64.5% implied probability, reflecting the district’s partisan baseline tempered by his polarizing profile and Gendebien’s localized appeal ahead of the November 3 vote.